Technical Abstract:
Water-soluble materials are widely used in the applications of agriculture, food and pharmaceuticals. The objective of this study was to investigate a new microencapsulation method to produce water-soluble materials. A high-voltage electrostatic field apparatus was used to produce such materials represented by water-oil-water multiple-layer emulsion. The inner solution was distilled water which was deputized as water-soluble materials, the oil phase was liquid paraffin, and the external aqueous phase was sodium alginate (NaAlg) solution. Influences of voltage, distance between pinhead and reaction liquid surface, pushing speed, prime emulsion/external aqueous, and NaAlg concentration on microcapsule sizes were studied. The results indicated that voltage, distance and NaAlg concentration had much greater influences than other studied factors. The optimum conditions of microencapsulation were voltage of 3.0~4.0kV'distance of 2.5~5cm and NaAlg concentration of 0.6~1.2%. The sizes of obtained microcapsules ranged from 50 to 1000 µm in diameter. It was concluded that water-soluble materials could be microencapsulated using the emulsification and high-voltage electrostatic field method to achieve various sizes and shapes.